Elastic container with reciprocating plunger



Aug. 4, 1959 B. F. GASSAWAY ELASTIC CONTAINER WITH RECIPROCATING PLUNGERFiled Jan. 17, 95

INVENTOR. Benjamin E'Gassaway ELASTIC CONTAINER WITH RECIPROCATINGPLUNGER Benjamin F. Gassaway, Milwaukie, reg., assignor, by mesneassignments, to Flo Container incorporated, a corporation of WashingtonApplication January 17, 1956, Serial No. 559,549

4 Claims. (Cl. 222-212) My invention is directed to improvements inflexible walled containers, particularly of the dispensing type. It isparticularly designed for storing and dispensing various types offluids, pastes, creams and medicaments, which are usually quite viscous.That is, my invention is particularly directed to dispensing containersfor materials which are not so fluid or-comminuted that they can bedispensed by being atomized or discharged by pouring, shaking, tilting,jarring or vibrating, or the like.

In the past, so far as I know, such materials have commonly beenpackaged in jars, from which this material must be removed digitally orby use of an instrument, or have been contained in a collapsible anddeformable container, or one which can be sequentially stripped touncover the undispensed portion thereof, or housed in sectional,telescopically arranged containers comprising multiple parts which maybe moved longitudinally relatively to eject said materials.

I have discovered that a satisfactory container for this purpose may bedevised with deformable and elastic walls, enclosing a follower.Apertures and valves therefor are arranged so that when the walls aredeformed, and thereafter permitted to spring back to their originalshape, subatmospheric pressures may be produced and the elasticity ofthe Walls will cause the follower to move up and displace the materialwhich has theretofore been ejected.

The object of my invention is to provide an elongated container havingflexible and elastic walls, in Whole or in part, provided with a valveddispensing spout at one end thereof and a bleeder vent at the other.Said container preferably should have its major portion of uniform crosssection, and Within said container, or within a major portion thereof, afollower is arranged and is proportioned to conform and be guided by theinner wall of the container to maintain the material more or lesscompact. It is essential that the dispensing spout or aper ture have avalve thereon which permits the material to flow outwardly from thecontainer but inhibits reverse air flow therein. At the other side ofsaid follower, a vent must be provided to the atmosphere so that air atatmospheric pressure may readily flow into the container below saidfollower. Then when external digital pressure is exerted against theflexible and resilient wall portions of the container, it will cause apoition of the material therein to be expressed from the dispensingspout, and when pressure is relaxed, the walls will regain their normalcontour and produce subatmospheric pressures. The follower then moves upuntil pressures are equalized. Successive deflections of the wallportionswill dispense material until said material is completelydischarged from the container.

A further object of my invention is to provide a container of thischaracter which, though subject to repeated flexure, is not deformed byuse and thus is capable of being refilled and reused.

A further object of my invention is to provide a con- 2,898,007.fatented Aug. 4-, 1959 ice tainer of this general character whichresembles a piston and cylinder, but in which the piston is advanced notby providing pressures below the piston of such amplitude aboveatmospheric pressure that the piston is moved thereby but by producingsubatmospheric pressures adjacent the material to be dispensed andthereafter permitting the follower to rise in response thereto untilatmos pheric pressure conditions are attained.

Further and other details of my invention are hereinafter described withreference to the accompanying drawings, in which:

Fig. 1 is a view of a dispensing container embodying my invention,illustrating the manner in which the walls may be flexed to expressmaterial from the dispensing spout;

Fig. 2 is an elevation of said container, with the walls arranged inunflexed condition and with portions of said container shown broken awayto disclose, in section, the details thereof;

Fig. 3 is a sectional view taken on the line 33 in Fig. 2, showing thedetails of a valved bleeder vent by which air under atmospheric pressuremay flow into the container from below the follower;

Fig. 4 is a plan view of the dispensing end of said container;

Fig. 5 is a sectional view, taken on the line 55 in Fig. 4, showing saiddispensing spout open; and

Fig. 6 is a view similar to Fig. 5 showing said dispensing spout closedand sealed.

A container embodying my invention preferably is made of a material suchas polyethylene plastic, which is capable of distortion without ruptureand which has suflicient elasticity to return it to its original shapewhen external pressures are relaxed. In the drawings, said container 1is shown to be of cylindrical fonn, with a flexible wall 2, a base end3, and a top or dispensing end 4. Said container preferably is elongatedand should be of uniform cross section throughout all, or through asubstantial portion, of its length. Said container may be of any crosssectional pattern, such as square, rectangular, triangular, elliptical,or other desired pattern.

Within said container is a follower 5. The peripheral outline of saidfollower conforms closely to the cross section of the container. Saidfollower must be relatively stiff and lit snugly within the bore of thecontainer. A polyethylene plastic container is capable of stretchingwithin a limited range, and thus I prefer to make the follower slightlyoversize with respect to the bore of the container, so that theperipheral skirted portion 5a of the follower bears tightly against thebore of the container in good air sealing relation therewith. Theskirted periphery of said follower should be quite broad so that saidfollower will not tend to cant or wedge within the container when theflexible wall of the container is flexed to discharge materialtherefrom. Said follower has one face 5b which is complementary to, thatis, intaglio with the conformation of the top or dispensing end 4. Thispermits all of the material within the container lying above thefollower to be forced outwardly from the container with no substantialresidue.

The base end 3 should be relatively stiff so as to maintain theconformation of the flexible wall. It also provides a base upon whichthe container may stand. Centrally of said base is a vent or bleederaperture 3a over which is arranged a flapper valve 6. As is shown inFig. 3, said valve is tacked or secured to the base only partially aboutits periphery as at 6a, thus leaving two diametrically disposedpassageways 6b through which air at atmospheric pressure may pass fromthe exterior through said .vent or aperture 3a to the space below thefollower 5. Reverse flow through said vent or bleeder aperture 30 isinhibited, however, because the flapper valve will 3 lie'flatwiseover'the aperture and'will hold said'valve tightly as a check valve toprevent said reverse flow. Any typeof check valve may be usedinconnection with said vent 3a, but a flap er type, as' illu'stra'ted, hasproved satisfactory in practice.

'The top or dispensing end o'fthe'con'tainer is also shown' to be ofheavier section than the wall. 'In some cases, this is desirable, and inothers it-is 'desirable'that the top be of the same or substantially thesame flexibility and elasticity as possessed by the wall. Two heavierends tend to cause the container better to retain its cylindrical form,but I have found'that one stiff end, such as the base 3, is adequate tomaintain said rotundity as shown in the drawings particularly when thefollower is similarly made stiif andtraverses the length of thecontainer. A snout or neck 7 is. preferably formed integral with the topor dispensing end 4, and usually is provided w-itlran outstanding flangeor other corrugation 7a so that a dispensing valved cap 8 may besecurely held'thereon.

The dispensing valve cap illustrated in the drawings is of the typedisclosed in my United States Patent No. 2,623,663, issued December-30,1952 and entitled -Suction Cup Dispensing Spou Briefly, said dispensingcap is forced into sealing positionwhen pressures within'the containerare elevated, tending to discharge material-therefrom. This flows fromthe presence ofa pair of opposed suction cups which face each other andwhich are forced towards each other by elevated pressure acting upon theexterior faces of lips 8a. This is shown most clearly 'in Figs. and 6.When elevated pressures exist within the container, they act upwardlyand inwardly against the lips 8a and cause the suction cups to distortand produce a suction seal such as is shown in Fig. 6. This seal may bebroken by digitally forcing the margins inwardly to release said partialvacuum or decreased pressure between the two suction cups 80. When saidreduced pressure is relaxed, the parts tend to open up and separate, asis shown in Fig. 5. This permits material readily to flow between saidsuction cups and outwardly in the manner illustrated in Fig. 1. Whensufficient material has been dispensed, said suction cups will be forcedtogether manually and the dispensing valve cap serves as astopper to.prevent further discharge of material. I preferably make :said valvecap 8 out of a rubbery material such, for example, as a vinyl plastic,synthetic rubber, or similar -materials. I have also found that a vinylplastic will .make an integral container including said dispensing valvecap. When the parts are thus made integral, it is not necessary to haveasnout or neck, and the top or dispensingend of the container mergesinto the valve cap 8.

In'use, the valve cap 8 is-opened by applying pressure, usually exertedby the-forefinger and the thumb, edgewise of the cap. This forces theparts to separate to the positron shown in Fig. 5. Viscous material maythen be #forc'ed from thecontainer by flexing the flexible and elasticwalls-in the manner shown in Fig. 1.

--Thecross sectional area of said container is'such that suflieientmaterial may be dispensed by a single pressing. If more material is tobe dispensed, it'is necessary to seal the spout,-in-the manner shown inFig.6, 'so as to'permit the follower-to move-upwardlytoaccommodateitself to the material previously dispensed. The followermoves "upwardlywhen the walls resume'their original'undist'orted*shapebecause a-region of'subatmospheric pressure is'pro- -v1dedbetween'the follower 5 and the top or dispensing end 401?the-containe=r, and the follower moves up until pressura'equilibn'umisreached. The flapper valve per- -rnrtsair to flow into the spacebelow'the follower valve tliIlHl'ht'InQSpllm'lC pressure is attainedbelow the follower. I have used this-dispensing container with variousmatefrials such as'shaving cream,tooth paste; ointments, salves, andeven with *materials'of such viscosity as Vaseline. Its preferable'range'of use "is with semi fluid materials having a viscositysomewhatabove a'state of fluidity at which they will flow readily under normalconditiqns but with 'insufiicient fluidity 'to flow from an apertureby'shaking, vibrating or other manipulation.

When the contents of said container have been entirely dispensed, it maybe refilled by merely holding the flapper valve 6 open and by removingthe dispensing valve cap 8. Materials filling the space above thefollower S will fill the container, and thereafter the dispensing valvecap may be replaced.

I claim:

1. A dispensing device for viscous liquid materials comprising anelongated container of uniform cross-section throughout a substantialportion of its length having flexible and-resilient side walls along itslongitudinal dimension, a floating stiff plunger element free totraverse the longitudinal dimension of said container, said plungerelement dividing the interior of said container into two compartments,each of said compartments being unobstructed across its entiretransverse dimension, one adjacent each end of the container and eachsubstantially sealed from the other, a valve controlled air inlet at oneend of said container for introducing air into the compartment adjacentsaid one end, and a liquid dispensing spout at the other end ofsaid-container for discharging liquid from the other compartment, saidliquid dispensing spout having an aperture extending therethroughcommunicating at its inner end with said other compartment and a valvestructure having flexible and elastic wall elements for closing saidaperture by constriction of a portion of said aperture, said valvestructure accommodating unidirectional flow of liquid from the'interiorof said other compartment to the atmosphere, said aperture being theonly passage leading from the interior of said other compartment to theatmosphere.

2. A dispensing device for viscous liquid materials comprising anelongated container of cylindrical crosssection throughout a substantialportion of its length having flexible and resilient sidewalls along itslongitudinal dimension, a floating stiff plunger element of cylindricalshape free to traverse the longitudinal dimension of said container,said plunger element dividing the interior of said container into twocompartments, each of said compartments being unobstructed across itsentire transverse dimension, one adjacent each end of the container,said plunger element having a relatively broad peripheral rim portionsnugly sliding 'within the interior of said container and substantiallysealing each of said compartments from the other, a valve-controlled airinlet at one end of said container for introducing air into the'compartment adjacent said one'end, and a liquid dispensing spout at theother end of said container for discharging liquid from theother-compartment, said'liquid dispensing spout having an apertureextending therethrough communicatingat its inner end with said othercompartment and a valve structure having flexible and resilient wallelements for closing said aperture by constriction of a portion of saidaperture, said valve structure accommodating unidirectional flow ofliquid from the interior ofsaid other compartment to the atmosphere,said. aperture being the only passage leading from the interior of saidother compartment to the atmosphere.

3. A dispensing device for viscous 'liquid materials comprising anelongated container ofuniform cross-section throughout a substantialportion of its length having flexible and resilient side walls along itslongitudinal dimension, said container having a stiff end wall at oneend thereof, a floating stiff plunger element free to traverse thelongitudinal dimension of said container, said plunger element dividingthe interior of said container into two compartments, each of saidcompartments being unobstructed across its entire transverse dimension,one adjacent each end of the container and each substantially sealedfrom the other, a valve controlled air inlet at said one end of saidcontainer extending through said end wall for introducing air intothe'compartment adjacent said one end, and a liquid dispensing spout atthe other end of said container for discharging liquid from the othercompartment, said liquid dispensing spout having an aperture extendingtherethrough communicating at its inner end with said other compartmentand a valve structure having flexible and elastic Wall elements forclosing said aperture by constriction of a portion of said aperture,said valve structure accommodating unidirectional flow of liquid fromthe interior of said other compartment to the atmosphere, said aperturebeing. the only passage leading from the interior of said othercompartment to the atmosphere.

4. A dispensing device for viscous liquid materials comprising anelongated container of uniform cross-section throughout a substantialportion of its length having flexible and resilient side Walls along itslongitudinal dimension, a floating stiff plunger element free totraverse the longitudinal dimension of said container, said plungerelement dividing the interior of said container into two compartments,each of said compartments being unobstructed across its entiretransverse dimension, one adjacent each end of the container and eachsubstantially sealed from the other, said container having a stiffcircular end Wall at one end thereof, a valve controlled air inlet atsaid one end f said container extending through said end wall forintroducing air into the compartment adjacent said one end, and a liquiddispensing spout at the other end of said container for dischargingliquid from the other compartment, said liquid dispensing spout havingan aperture extending therethrough communicating at its inner end Withsaid other compartment and a valve structure having flexible and elasticwall elements for closing said aperture by constriction of a portion ofsaid aperture, said valve structure accommodating unidirectional flow ofliquid from the interior of said other compartment to the atmosphere,said aperture being the only passage leading from the interior of saidother compartment to the atmosphere, the face of said plunger elementfacing said dispensing spout conforming to the inner tape of said otherend of said container.

References Cited in the file of this patent UNITED STATES PATENTS1,595,889 Stevens Aug. 10, 1926 1,854,458 De Quincy et a1 Apr. 19, 19322,329,917 Lautmann Sept. 21, 1943 2,623,663 Gassaway Dec. 30, 19522,743,042 Burgin Apr. 24, 1956 2,802,608 Gassaway Aug. 13, 1957 FOREIGNPATENTS 298,008 Switzerland June 16, 1954

